Angle-cock device



June 24, 1930. FARMER 1,765,578

ANGLE COCK DEVICE Filed Nov. 24, 1928 INVENTOR CLYDE C. FARMER ATTORNEYPatented June 24, 1930 UNITED STATES PATENT OFFICE CLYDE C. FARMER, OFPITTSBURGH, PENNSYLVANIA, ASSI-G-NOR TO THE WESTING- HOUSE AIR BRAKECOMPANY, OF WILMERDING, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIAANGLE-COCK DEVICE Application filed November 24, 1928. Serial No.321,546.

This invention relates to fluid pressure brakes and more particularly toan angle cock device for opening communication through the brake pipewhen two train sections are connected together.

One object of the invention is to provide an angle cock device having aby-pass valve controlled by means which are automatically actuated whenthe plug valve of the angle cock is opened slightly to permit the fluidfrom a charged train section to flow into an uncharged train sectionwithout causing a too rapid rate of decrease in brake pipe pressure onthe charged portion of the brake pipe.

Another object of the invention is to provide an angle cock device ofthe type specified with means for measuring the time between thecracking of the angle cock plug valve and the Wide opening thereof topre vent a sudden drop in the fluid pressure of a charged brake pipewhen an uncharged train section is coupled to a charged section.

Another object of the invention is to provide an angle cock device ofthe character mentioned which is simple in construction and reliable andexact in function under all conditions of service. 1

The invention also comprises certain me and useful improvements in theconstruc tion, arrangement and combination of the several parts of whichit is composed, as will be hereinafter more fully described and claimed.

In the accompanying drawing, the single figure is a diagrammaticsectional View of an angle cock device embodying my invention.

In cutting an uncharged section of a train into a charged section, it iscustomary to crack open the angle cock plug valve to permit theuncharged section of the train to charge, the opening through the anglecock being such as to prevent a too rapid rate of decrease in brake pipepressure on the charged portion of the brake pipe. A sudden drop inbrake pipe pressure would cause undesired emergency in the chargedsection of the train.

Some train men are capable of so opening the angle cock as to cause thebrake pipe pres sure to drop in the charged portion of the train at sucha rate as to cause a service re duction, even though the feed valvetends to maintain the brake pipe pressure against such flow. When abrake pipe reduction of possibly eight pounds is thus obtained on threeor four cars adjacent the uncharged section of the train, then the anglecock can be opened wide without causing undesired quick action. This isdue to the triple valves having moved to service position against thegraduating spring, in which position an increased ditferential over thetriple valve piston is required to move the triple valve piston toemergency position. This increased differential is hard to obtain,especially on-account of the wide opening of the service port whichpermits a rapid rate of drop in the auxiliary reservoir pressure. Alsothe brake cylinder pressure obtained in service acts on the quick actionpiston of the triple valve in such a manner as to tend to prevent suchpiston from acting even if the triple valve did go to emergency.

By my present invention, an angle cock device having a by-pass that isnormally closed by a valve piston is provided with pneumatic means whichare operated by the variation of the fluid pressure on one side of thevalve to open and close the bypass valve of the angle cock, so that atime period, proportional to the pressure in the charged section of atrain, is required between the cracking of the angle cock plug valve andthe wide opening thereof to prevent a sudden rate of drop of the brakepipe pressure in the charged train section until the fluid pressure inthe uncharged section coupled thereto has been built up a predeterminedamount.

As shown in the drawing, the angle cock device may comprise a casing 1containing the usual plug valve or key 2 adapted to be operated by theusual handle (not shown). The valve 2' is provided with a passage 8adapted in the open position of the valve to connect the conduit 4 atthe brake pipe end of the angle cock with the conduit 5 at the flexiblehose end. The valve 2 has a side port 6 0 en to conduit 5 when the valveis closed.

ssociated with the casing 1 is a cylinder 7 containing a valve piston 8adapted to control a by-pass 9 through an opening 10 having a seat rib11. At one side, the valve piston 8 is subject to the pressure of a coilspring 12. At the end of a train, the valve piston 8 is held seatedagainst the seat rib 11 by the spring 12 and intermediate the ends of atrain the valve piston is opened by the pressure of the brake pipe fluidacting over its entire area.

A chamber 13 formed in the casing contiguous to the cylinder 7 isconnected to the plug valve 2 by a passage 14 and to the outer end oithe cylinder 7 by a passage 15.

The cylinder 7, at the spring side of the valve piston 8, is connectedto another cylinder 16 by a passage 17 having a vent 18 therein open tothe atmosphere. The flow area of the passage 14 is greater than that ofthe vent 18 so that a pressure can be built up in chamber 13 for apurpose to be described.

The outer edge of the valve piston 8 is formed with a seat rib 19adapted to engage a gasket 20 in the head of the cylinder and close thepassage 15 when the valve piston is unseated from the seat rib 11.

Mounted in the chamber 21 of cylinder 16 is a hollow piston 22 whichterminates at its rear end in anenlarged piston 23 that is disposed inthe chamber 24 of a cylinder 25 of greater diameter thanthe cylinder 16.

At. one side, the piston 22 is subject to the pressure of a coil spring26 which encircles a stem 27 carried by the head 28 of cylinder 25.

The piston 23 is provided with a cup packing 29 adapted to seal the headof the piston with the, wall of the cylinder 25 when the piston 22 isforced outwardly, so that the fluid will be retained in chamber 24 forthe purpose or" retarding or cushioning the action of piston 22. It willthus be noted that the cylinder 25 and piston 23.constitute a dash potwhich functions in a manner to be described to prevent a too rapid rateof decrease in brake pipe pressure in the charged portion of the brakepipe when two train sections are being connected together.

Near one end, the wall of the cylinder 16 is provided with a pluralityof ports 30 which vent to the atmosphere through a pas sage 31 formed inthe wall ofthe cylinder,

29, the ports 30 and vent 31 communicating with a chamber 32 on the sideof the piston 23 opposite to the chamber 24. ;Agroove 33 is formed inthe wall of the chamber 24 near the head 28 of the cylinder 25. Theports 30 and the groove 33 are so disposed that when the pistons 22 and23 are at the outer end of their stroke the head of the piston 22 willexpose the ports 30 to permit In connecting a charged section of trainto an uncharged section, the plug valve 2 is turned from closed towardopen position an amount suflicient to only permit a slow drop inpressure in the conduit 4. Fluid pressure from the conduit 4 flowsthrough the passage 3 and conduit 14 to chamber '13.

Since the valve piston 8 is seated on the seat rib 11, fluid from thechamber 13 flows through passage 15 into the chamber 34 and thencethrough passage 17 to the atmosphere by wayof the vent 18 and also intothe cham ber 21 and thereby acts on piston 22.

The flow area of conduit 14 is greater than that ofthe vent 18, so'thatpressure can be built up in chambers 13 and 34 to retain the valvepiston 8 seated on the seat rib 11 to close the opening 10.

As the fluid pressure in the chamber 13 builds up, the pressure ofthefluid in chamber 21 will also buildup to a point suflicient to causepistons 22 and 23 to gradually move outwardly. This action compressesthe fluid in chamber 24, which normally is at atmospheric pressure, soas to increase the resistance to the piston movement. However, thepressure of the fluid in chamber 21 gradually increases, so that piston22 will be moved an amount suflicient to uncover the ports 30.

The capacity of the ports 30 is greater than 2.".

the capacity of the'conduit 14, so that the pressure is suddenly ventedfrom the chamber 34, thereby permitting the fluid under full pressure inthe train pipe to force the valve piston 8 from the seat rib 11.

After the valve piston 8 is unseated from the seat rib 11, the plugvalve 2 can be opened wide, to the position shown in the drawing,without causing any undesired eflect.

When the pistons 22 and 23 reach their extreme outward positions, thepressures are suddenly balanced on the opposite sides thereof throughthe groove 33, so that after the plug valve 2 is opened and the passage17 thus lapped, the pistons 22 and 23 are gradually returned to normalposition by spring 26. In this way the return of these pistons isretarded more than would be the case if the pressure built up by theoutward movement of piston remained effective in chamber 24.Furthermore, it would be undesirable to have the pistons 22 and 23suddenly returned to their normal position as would occur if the builtup pressure in chamber 4 was not vented, because a sudden returnmovement of pistons 22 and 23 would tend to increase the pressure offluid in the chamber 34, thereby causing the valve piston 8 to return tothe seat rib 11. The value of spring 26 is such as is necessary to movethe pistons 22 and 23 against the resistance of friction, and thereforein the outward movement of these pistons has no. appreciable eflectthereon.

If two trains, or two sections of a train are brought together, and bothsections are charged, the uncharged volume in the connecting hoses issuflicient to cause quick action it the angle cock at either end issuddenly opened. Therefore, the angle cock on one car is operated in themanner described above, to time the opening of the valve piston 8 inthat angle cock. Since a build up of approximately five pounds pressurein the hose and on the face of the valve piston 8 outside the seat rib11 in the angle cock of the other car is suflicient to open the by-passvalve of such car, undesired emergency would thus result in spite of thetimed operation of the other by-pass valve.

In order to prevent this action, air flowing into the hose from thefirst angle cock is per mitted to flow through port 6 in the plug valve2 of the second angle cock which is in closed position, in whichposition passage 3 registers with the conduit 14:, and thus equalizesthe fluid pressure acting on the valve piston 8 so as to prevent theopening of the valve piston 8 until the piston 22 operates to vent thechamber 34 of the second angle cook.

The hose thus becomes substantially charged before the brake pipe of thetwo portions of the train become connected.

It will be noted that the outward travel of pistons 22 and 23 dependsupon the rate of pressure built up in chamber 21. Since the rate ofcharging the uncharged section of a train depends upon the pressure headof the fluid pressure supply in the charged portion of the train, it isobvious that the rate of operation of the timing element may vary inproportion to the head of the fluid pressure supply, so that withvarying brake pipe pressures the timing element will always operate toopen the bypass valve as soon as possible, that is to say, with a highbrake pipe pressure head the pistons 22 and 23 will be actuated quickly,and with a lower brake pipe pressure head it will require a longer timeto move these pistons to their extreme outward position.

While one illustrative embodiment of the invention has been described indetail, it is not my intention to limit its scope to that embodiment orotherwise than by the terms of the appended claims.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent, is

1. A device of the class described comprising a cock, and having apassage for establishing communication from one side of the cock to theother, valve means for the passage, and pneumatic means for actuatingthe valve means when the pressure of fluid at one side of the cockincreases or decreases a predetermined amount.

2. A device of the class described comprising a cock, and having apassage for establishing communication from one side of the cock to theother, and means actuated automatically by the variation of fluidpressure on one side of the cock for opening and closing the passage.

3. An angle cock comprising a cock, valve means for controllingcommunication through a passage from one side of the cock to the other,and means for timing the action of the valve means.

4. An angle cock device comprising a cock, and having a passage forestablishing communication from one side of the cock to the other, avalve for controlling the flow of fluid through the passage, a chambercommunicating with the cock and with the valve, and means actuated bythe pressure of fluid in the chamber for timing the operation of thevalve.

5. An angle cock device comprising a cock, and having a passagepermitting the flow of fluid under pressure from one side of the cock tothe other, a cylinder communicating with the passage, a valve piston inthe cylinder for closing the passage, a chamber communicating with thecock and also with the cylinder whereby the pressure of fluid at oneside of the cock will act on the valve piston to close the passage, andmeans for reducing the pressure of fluid in the cylinder to release thevalve piston when the pressure of fluid in the chamber reaches apredetermined amount.

6. An angle cock device comprising a cock, and having a passagepermitting the flow oi fluid under pressure from one side of the cock tothe other, a cylinder communicating with the passage, a valve piston inthe cylinder for closing the passage, a chamber communicating with thecock and also with the cylinder,

and a dash pot actuated by the fluid pressure in the chamber for varyingthe amount of fluid pressure in the cylinder.

7. An angle cock device comprising a cock, and having a passagepermitting the flow of fluid under pressure from one side of the cock tothe other, a cylinder communicating with the passage, a valve piston inthe cylinder, a chamber communicating with the cock and also with thecylinder, and means actuated by the amount of pressure in the chamberfor actuating the valve whereby the passage is opened to permit the flowof fluid around the cock and the communication between the cylinder andchamber is closed.

In testimony whereof I have hereunto set my hand, this 22nd day ofNovember, 1928.

CLYDE G. FARMER.

